NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Helicopter impulsive noise - Theoretical and experimental statusThe theoretical and experimental status of helicopter impulsive noise is reviewed. The two major source mechanisms of helicopter impulsive noise are addressed: high-speed impulsive noise and blade-vortex interaction impulsive noise. A thorough physical explanation of both generating mechanism is presented together with model and full-scale measurements of the phenomena. Current theoretical prediction methods are compared with experimental findings of isolated rotor tests. The noise generating mechanism of high speed impulsive noise are fairly well understood - theory and experiment compare nicely over Mach number ranges typical of today's helicopters. For the case of blade-vortex interaction noise, understanding of noise generating mechanisms and theoretical comparison with experiment are less satisfactory. Several methods for improving theory-experiment are suggested.
Document ID
19870033921
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Schmitz, F. H.
(NASA Ames Research Center Moffett Field, CA, United States)
Yu, Y. H.
(NASA Ames Research Center; U.S. Army, Aeromechanics Laboratory, Moffett Field CA, United States)
Date Acquired
August 13, 2013
Publication Date
September 22, 1986
Publication Information
Publication: Journal of Sound and Vibration
Volume: 109
ISSN: 0022-460X
Subject Category
Acoustics
Accession Number
87A21195
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available